This invention relates to an apparatus and method for clearing of air conditioning drain lines. More specifically, it relates to a pump with a connection for clearing blocked condensate drain lines and drain pans on air conditioners and refrigeration equipment.
Air conditioning systems typically have evaporator coils that are used in the cooling of air to be distributed by the system through the building or area to be cooled. These evaporator coils collect condensate formed by humid air contacting the cold metal on the evaporator coils. Water in the humid air condenses on the coils, which then drips into a drain pan usually placed beneath the air conditioning system. The drain pan typically has an outlet connected to a pipe, which directs it to a drain, sewer system, or an outside area where water can drip without damaging the building.
The drain line from the drain pan frequently clogs due to algae or fungus growing in the lines or from debris blocking the drain line. If the drain line is completely blocked, the condensate can overfill the drain pan, spilling and causing water damage to a surrounding area. Sometimes the primary drain pan may be situated inside a secondary drain pan. A safety float switch may be positioned on the secondary drain pan so that, as that drain pan fills, the float switch will shut off the air conditioning system preventing further accumulation of water hence, damage from water spillage. Sometimes the drain pans are situated so spillage may not be noticed. For example, an air handler may be positioned in a crawl space in an attic area and, until the insulation is soaked through and the ceiling material is also soaked through, there would be little, if any, reason to know water spillage was occurring. However, at that point, substantial damage would have occurred before the drain line could be unblocked.
Blockages occur in other types of fluid-carrying lines, such as plumbing or industrial steam lines. Consequently, a variety of inventions are known in the art from such things as a plunger, sometimes called a plumber""s helper, or a plumber""s snake. Typically, these devices operate either by applying a mechanical force to a blockage, like a plumber""s snake, or by applying a hydraulic force such as a plunger. However, a heating and air conditioning drain line is typically made of a more delicate material than are water or sewage-carrying lines. Moreover, these drain lines are relatively small in diameter and may traverse relatively large distances from the air handler or evaporator coil where the condensation collects to the outside point where the condensation drains by means of the drain line. Consequently, things like plumber snakes or plungers are not helpful to clear blocked air conditioning drain lines.
Currently, a heating and air conditioning service technician has several options when confronted with a blocked drain line. He can clean out the drain pan and then apply air pressure or apply suction to drain pan end of the drain line in hopes of clearing a blockage, or he can cut the drain line in order to apply pressure or suction. This can lead to spillage from the drain line and a repair or partial replacement of the drain line is required after it is cut. Or at the drain end of the drain line he can apply pressure or suction. Most service technicians use his or her mouth to do this with potentially unpleasant or unhealthy consequences.
Several devices have proposed placing special valves in a drain line to facilitate the clearing of air conditioning drain lines. Potter, U.S. Pat. No. 6,608,023; Palmer, U.S. Pat. No. 6,041,611; Junkin, U.S. Pat. No. 5,964,238; and, Potter, U.S. Pat. No. 5,722,458, all propose placement of valves in a drain line to allow introduction of either a suction or air pressure or a hydraulic pressure to clear a drain line. Domansky, U.S. Pat. No. 5,666,690, proposes the use of a CO2 power device using a 12-gram CO2 cylinder to clear a drain line.
More generally, a variety of different types of pumps that induce either a pressure or a suction into a drain system are proposed for cleaning of drain lines. For example, Meyer, U.S. Pat. No. 2,697,842, proposes a combination hand and air force pressure pump and plunger for use generally in the same fashion as a standard plunger or plumber""s helper. Hasson, U.S. Pat. No. 635,961, also proposes using a cylinder with a piston to create either a pressure or suction used to clear pipes used for transporting of beer. Simmons, U.S. Pat. No. 999,346, proposes a specialized device for cleaning a smoking pipe. Despite this work there is still a need for a device to help unblock or clean a drain line for heating and air conditioning systems.
Most systems are not equipped with a valve as described in the Palmer ""611 or Potter ""023 and ""458 patents to facilitate introduction of a pressure or suction into a line. Consequently, a service technician would have to install such a valve or fall back on the expedients that have been employed in the past such as, cutting the drain line in order to induce a pressure or suction or use a mechanical cleaning device. Consequently, it would be an advance in the art to provide both an apparatus and a method, which can be used with standard heating and air conditioning units, to clean a drain pan and drain pipe that has become clogged. This invention consists of a rod connected to a piston inside of the cylinder. The rod and piston fits inside the circular cylinder and the piston is fitted with a gasket to slide within the inner circumference of the cylinder. There are connections at each end of the cylinder, with these connections designed for air and fluid-tight connections to hoses, pipes, or other connecting means. At one end of the cylinder that is connected to a drain pipe is an adjustable gasket-like fitting that will fit around in an air and fluid-tight manner to an end of the drain pipe. To use the device, a technician will go to the outside end of the drain pipe, connect the cylinder to the drain pipe after either all air or fluid has been exhausted from the cylinder or the cylinder has been filled with air or fluid, depending on the choice of the technician. One would then use the rod with the interior piston to create either a hydraulic pressure or a suction by moving the rod hence, the piston within the cylinder. This pressure or suction will be communicated by the connection to the drain pipe where the pressure or suction respectively created by the movement of the piston within the cylinder will be fluidly communicated to the drain pipe. This will create enough force to dislodge the obstruction in the drain pipe and to allow water to freely drain through the drain pipe into the outside area. The device may also be used to clear accumulated liquids from a drain pan or from an overflow drain pan. One could use the rod within the cylinder to fill the cylinder with liquid and then to expel the liquid into a container.